Histomorphological study of the parathyroid gland in female Kuttanad ducks (Anas platyrhynchos domesticus)

Abstract

Aim: The present work was targeted to form the baseline data of normal morphological and histological picture of parathyroid gland in female Kuttanad ducks.

Materials and Methods: A Histomorphological study of the parathyroid gland was carried out in twelve adult female Kuttanad ducks (Anas platyrhynchos domesticus) of 20 weeks of age. Birds reared semintensively were procured from Kerala Veterinary and Animal Sciences University Poultry and Duck Farm and sacrificed humanely. Glands were collected and gross parameters were recorded. The glands were fixed in 10 percent neutral buffered formalin. The small sized glands were processed as such by routine histological methods, paraffin blocks were prepared and sectioned to a thickness of 5µ. The tissues were stained by Haematoxylin and Eosin (H&E) for routine histological studies and Gomori's rapid one step trichrome method for connective tissue fibres. Micrometric parameters were recorded using ocular micrometer.

Results: Parathyroid glands in Kuttanad ducks lay just caudal to the division of the innominate artery into the subclavian and common carotid arteries. Parathyroids were oval to spherical in shape, yellow in colour and smaller than thyroid gland of the representative sides. The arterial blood supply was from common carotid artery and blood from gland was drained directly into jugular vein. Although it lied close to the thyroid, thymus and ultimobranchial gland, parathyroid tissue did not merge to any of the above mentioned three glands. Parenchyma was composed irregular anatomizing cords of cells supplied by connective tissue stroma penetrated by blood capillaries. Parenchyma was predominantly made of lightly stained cell, the chief cell. The nuclei were round and contain one or two nucleoli. Oxyphil cells present in parathyroid glands of other mammals were not seen in the present study.

Conclusion: Histomorphological features or characteristics of Parathyroid gland in Kuttanad duck were studied. Cranial parathyroids were larger in size as compared to the caudal parathyroids. Parathyroid glands were enclosed by a well-developed connective tissue capsule made predominantly of collagen fibers. Parenchyma was composed of irregular anatomizing cords of cells supplied by connective tissue stroma and penetrated by blood capillaries. Oxyphil cells were absent similar to other aves. Parathyroid gland is very vital in maintaining the homeostasis of the plasma calciumReference?. Findings of this study will contribute to the anatomy literature as a valuable resource for future researchers focused on this subject and will also help other allied subjects on comparative basis.